Posted 06 April 2011 - 07:35 AM

I have a Powerbook G4 (A1138) which does not recognise the Hard Drive.

I have tried a few drives with the same results... The Drive is not detected within Disk Utility.
I have swapped the ribbon cable connecting the drive to the logic board and still no joy.

Have also booted into Open Firmware and ran 'devalias HD' and the controller is listed regardless of whether the drive is connected. I don't know if this proves that the logic board is NOT faulty.

I don't want to waffle on too long but to cut a long story short, the Powerbook was purchased from a friend who had been swapping the drives between this Powerbook and another one he had.
After opening this Powerbook, I found that the ribbon cable that was attached to the HD wasn't the right part for this machine (according to the cable part number). I have since purchased the correct cable and fitted it and this is where I am now...

I have run an extended Apple Hardware Test and no issues were found, it passed on all tests.
Also, the same with Techtool Pro... Although... No HD's are discovered in Techtool to run any HD related tests.

I have since purchased an external firewire HD and have successfully installed OS X on this drive.
It appeared in Disk Utility and allowed me to erase and then install the OS.
The PB is running nicely on the external firewire drive but still have no idea why internal drives are not detected.

Just to add... I can get the PB to boot into Target Disk Mode and get the Firewire symbol on the screen. Don't know if this offers anything new to the equation?

Posted 07 April 2011 - 09:18 AM

Byrd

InsanelyMac Protégé

Members

12 posts

(the wrong cable) - what was it from, is there any evidence of components failing on the motherboard? Have you also checked for any damage to the new drive cable, and to the motherboard connector itself?

Posted 07 April 2011 - 05:58 PM

Payndemonium

InsanelyMac Protégé

Members

4 posts

(the wrong cable) - what was it from, is there any evidence of components failing on the motherboard? Have you also checked for any damage to the new drive cable, and to the motherboard connector itself?

Yes, when I first started diagnosing this PB I replaced the drive cable to eliminate it from the equation.

When I googled the part number of the drive cable which came with the machine, I discovered that the guy I bought it off had put the wrong cable in. (He had 2 PB's and was swapping drives between the two). I guess the cable that should have gone into this PB is in the other machine.

I bought a second user cable from an Apple parts supplier with the right part number for this PB and still have the same issue. It's possible that this cable could be faulty also, but didn't think the odds were that good.

I can't see any signs of damaged components on the logic board and the drive cable connector looks to be in good shape. There is a solid 'click' when the drive cable is plugged into the board which suggests that it is seated properly.

I'm scratching my head on this one... Could it be a faulty logic board?

I guess the next step is to buy a brand new drive cable and go from there.